Question

. If refractive index of glass is 1.68, What is the speed of light in glass. ? *

Answer 1

Answer:

$refractive \: index = \frac{speed \: through \: vaccum}{speed \: through \: medium} \\ 1.68 = \frac{3 \times {10}^{8} }{x} \\ = 1.7857 \times {10}^{8} \\ thank \: you$